A Hetnet (heterogeneous network) is a network including a micro base station and a macro base station (Macro).
In a Hetnet, soft handover is a handover process, a soft handover area refers to an area in which soft handover occurs, and an active set is a set of cells participating in a soft handover process of UE. When UE (user equipment) is located in a soft handover area of a macro base station cell and a micro base station cell, the macro base station cell and the micro base station cell are both located in an active set of the UE; and when the macro base station cell is a serving HS-DSCH (high speed downlink shared channel) cell, and the micro base station is a non-serving HS-DSCH cell, an RNC (radio network controller) may configure an F-DPCH (fractional dedicated physical channel) for the serving HS-DSCH cell and the non-serving HS-DSCH cell separately, and configure a first DPCCH (dedicated physical control channel) and a second DPCCH for the UE. The first DPCCH carries a TPC (transmit power control) command used to adjust transmit power of the F-DPCH of the non-serving HS-DSCH cell, and the second DPCCH carries a TPC command used to adjust transmit power of the F-DPCH of the serving HS-DSCH cell.
In the prior art, an active set of UE generally includes one serving HS-DSCH cell and one non-serving HS-DSCH cell; an RNC delivers a target TPC error rate to the UE. The UE acquires a target F-DPCH SIR (signal-to-interference ratio) corresponding to the target TPC error rate; then measures an F-DPCH of the serving HS-DSCH cell and that of the non-serving HS-DSCH cell to obtain a measured F-DPCH SIR of the serving HS-DSCH cell and a measured F-DPCH SIR of the non-serving HS-DSCH cell, and separately compares the measured F-DPCH SIR of the serving HS-DSCH cell and the measured F-DPCH SIR of the non-serving HS-DSCH cell with the target F-DPCH SIR. The UE generates, according to a comparison result, a first TPC command for adjusting transmit power of the F-DPCH of the serving HS-DSCH cell and a second TPC command for adjusting transmit power of the F-DPCH of the non-serving HS-DSCH cell. Subsequently, the serving HS-DSCH cell adjusts the transmit power of the F-DPCH of the serving HS-DSCH cell according to the first TPC command, and the non-serving HS-DSCH cell adjusts the transmit power of the F-DPCH of the non-serving HS-DSCH cell according to the second TPC command.
However, if the active set of the UE includes one serving HS-DSCH cell and multiple non-serving HS-DSCH cells, because an F-DPCH is configured for each non-serving HS-DSCH cell, the UE cannot determine an F-DPCH of which non-serving HS-DSCH cell should be measured, and therefore cannot generate a corresponding TPC command for any non-serving HS-DSCH cell.